Ultrasonic signal generator



June 27, 1967 D. INMAN 3,327,679

ULTRASONIC SIGNAL GENERATOR Filed April 8. 1966 '2 Sheets-Sheet 1 FIG.1 FIG.2

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64 Dorwm lnmon 60 J l 7 I" I I4 59 74 as 66 887E186 Attorney June 1967 D. INMAN 3,327,679

ULTRASONIC SIGNAL GENERATOR Filed April 1966 2 Sheets-Sheet 2 2s 2e FG.3

INVENTOR. D0 rw n l n me n BY J i I 1 Attorney United States Patent 3,327,679 ULTRASONIC SIGNAL GENERATOR Darwin Inman, Highland Park, 111., assignor to Zenith Radio Corporation, Chicago, 11]., a corporation of Delaware Filed Apr. 8, 1966, Ser. No. 541,216 7 Claims. (Cl. 116137) The present invention rel-ates to a portable signal generator of the type having a mechanical vibrator element for generating an ultrasonic signal and, more particularly, to a new and improved mechanism for imparting mechanical energy to the vibrator element to set it into vibratory motion.

Ultrasonic transmitters for use is remote control systems are well known in the television art. These transmitters generally produce an ultransonic signal by striking or otherwise exciting a vibrator element, which signal is received and amplified by a receiver within a television set and utilized to remotely control any of a plurality of desired functions. An example of such a transmitter is described and claimed in US. Patent 3,118,423 issued to Schmid and assigned to the assignee of the present invention. In a transmitter constructed for operation in this manner, the desirability of reduced size and weight is apparent when it is appreciated that the transmitter is intended to be held and operated with only one hand so that the user need not divert his attention from the television set during operation of the transmitter. It is also apparent that the transmitter should be constructed to provide long and continuous service without mechanical failure.

Accordingly, an object of the present invention is the provision of an ultrasonic signal generator having a unique mechanical actuating mechanism.

Another object is to provide an ultrasonic signal generator which is capable of providing long and continuous service without mechanical failure.

A further object of the invention is the provision of a signal generator having a new and improved mechanism for delivering mechanical energy to the vibrator element therein.

Still another object of the invention is to provide a portable ultrasonic signal generator having a mechanical actuating mechanism which permits a substantial and effective reduction in the complexity of the transmitter without in any way interferring with the operation thereof.

Yet another object of the present invention is the provision of an ultrasonic signal generator which is characterized by simplicity of construction, low cost and ease of operation and use.

In accordance with the present invention, a portable hand-held signal generator for use in a remote control system comprises mechanically excitable vibrator means, a support member having a guide channel with an opening terminating adjacent the vibrator means, and a hammer slid'ably received within the guide channel. "In addition, means are provided for captivating the hammer within the guide channel and a shaft is secured to the support member with a striker means pivotally mounted thereon. Spring bias means associated with the striker means urge the striker means towards the hammer while actuator means pivotally mounted on the sh-a'ft are provided for rotating the striker means against the urging of the spring bias means. Trip means are mounted upon the actuator means for releasing the striker means after rotation thereof through a predetermined angular displacement to allow the spring bias means to rotate the striker means and cause the hammer to be propelled through the guide channel and into contact with the vibrator means for initiating vibrations therein.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The organization and manner of operation of the invention, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings, in the several figures of which like reference numerals identify like elements, and in which:

FIGURE 1 is a plan view, partly broken away and partly in section, of a preferred embodiment of the invention;

FIGURE 2 is a side view of the device, partly in section, taken on the lines 22 of FIGURE 1 looking in the direction of the arrows;

FIGURE 3 is a partial sectional view of the device shown in an unactuated position taken on the lines =3-3 of FIGURE 1 looking in the direction of the arrows;

FIGURE 3a is a view similar to FIGURE 3 but show.- ing the device of FIGURE 1 in a partially actuated position;

FIGURE 4 is an end view of the device, partly in section, taken along the lines 4-4 of FIGURE 1 looking in the direction of the arrows;

FIGURE 5 is a detailed perspective view, partly broken away, of the actuator mechanism of the present invention; and

FIGURE 6 is a detailed perspective view of the support member of the present invention.

Referring now to the drawings, there is shown in FIG- URES l and 2 a portable hand-held ultrasonic signal generator 10 having a housing 12 of convenient size and shape to afford easy holding and manipulation by the user. The housing 12 comprises a top panel 14 and a bottom panel 1'6, both of the panels having rounded edges which form the side portions of the housing. The housing 12 is closed at its rear end 18 by overlapping portions of the top and bottom panels 14 and 16, respectively, while the front end 20 of the generator 10 is open except for a screen 22 disposed thereacross. The screen 22 is secured to the housing 12 'by grooves 24 formed in the top and bottom panels '14 and 16. A plurality of openings 26 are provided in the top panel 14 through which a plurality of manually operable push buttons 28 protrude. Although there are four independent signal generating mechanisms shown in the drawings, only one complete mechanism will be described for purposes of simplicity of description.

The ultrasonic signal generating mechanism is mounted within the housing 12. More particularly, a bracket 30 is secured to the top panel 14 by a threaded fastener 32 and to the bottom panel 16 by a threaded fastener 34. Vibrator means comprising an elongated cylindrical metallic vibrator rod 36 is secured to the bracket 30 by a spring clip 38 engaging a pair of slots 40 formed at the nodal plane of the vibrator rod 36, as described and claimed in US. Patent 2,821,956 to Wold, assigned to the same assignee as the present application.

A support member 42 is secured in the housing 12 near the rear end 18 by a pair of threaded fasteners 44 passing through the bottom panel 16 and engaging threaded apertures 45, and by a pair of threaded fasteners 46 passing through the support member 42 and engaging threaded apertures 47 in the top panel 14. The support member 42, as best illustrated in FIGURE 6, comprises a unitary block of a suitable material, such as plastic, having four cylindrical guide chanels 48 formed therein. A plurality of permanent magnet captivating means 50 are disposed in slots formed within the support member 42 on either side of each of the guide channels 48, and a cylindrical hammer 52 (see FIGURES 3 and 3a), formed of ferromagnetic material, is slidably received within each of the guide channels 48. Each guide channel 48 terminates in an opening 54 adjacent the end of the vibrator rod 36 and is spaced a predetermined distance therefrom. The vibrator rods 36 are of diiferent lengths to produce signals of different frequencies when set into longitudinal-mode vibratory motion. Therefore, the guide channels 48 formed in the support member 42 are of different lengths corresponding to the length of the respective vibrator rod 36 associated therewith so that the overall length of the housing 12 may be kept to a minimum. The permanent magnets 50 establish a magnetic field traversing the guide channel 48 to magnetically captivate the ferromagnetic hammers 52 within the guide channels 48 as described and claimed in US. Patent 3,118,423 to Schmi-d. In addition, each of the ferromagnetic hammers 52 has an axial length greater than the predetermined distance between the opening 54 of the guide channel 48 and the end of the vibrator rod 36 so that the hammer 52, when striking the actuator rod 36, is retained at least partially within the guide channel 48. 7

Referring now to FIGURES 3 through 6, a shaft 56 is secured to the support member 42 by means of a pair of counterbored apertures 58 formed at the sides of the support member 42 and slotted as at 59. One end of the shaft 56 has a head 60 formed thereon and the other end of the shaft 56, after being assembled onto the support member 42, is provided with a washer 62 and then swedged as at 64 to prevent Withdrawal through the washer. A plurality of manually operable actuator mechanisms are pivotally mounted on the shaft 56 to selectively and independently cause any selected hammer 52 to be propelled through the guide channel 48 and into contact with its associated vibrator rod 36.

As illustrated in FIGURES 3 and 5, each of the actuator mechanisms comprises a bell crank striker 66 having a first leg 68 and a second leg 70, the bell crank striker 66 being pivoted on the shaft 56 intermediate the legs 68 and 70. The first leg 68 of the bell crank striker 66 passes through a slot 72 in the guide channel 48 and is urged into engagement with the forward edge of the slot 72 by means of a spring 74 coiled around the shaft 56 and engaging a lug 76 formed on the support member 42 and a recess 78 formed within the second leg 70. Therefore, as illustrated in FIGURE 3, the bell crank striker 66 is biased by the spring 74 in a counterclockwise direction. The end of the second leg 78 of the bell crank striker is provided with a rounded surface 80 and a flat surface 82, the purpose of which will be hereinafter set forth.

An actuator in the form of a bifurcated lever 84 having a pair of arms 86 and 88 is pivotally mounted upon the shaft 56, the arms 86 and 88 being disposed on opposite sides of the bell crank striker 66 so that the second leg 70 of the bell crank striker 66 lies between the arms 86 and 88. The push button 28 is secured to one of the bifurcated lever 84 by a threaded fastener 90 threadedly engaging an aperture 92 in the base of the push button 28. Trip means in the form of a latch 94 is slidably received within the bifurcated lever 84 and is spring biased by a spring 96 in a direction towards the shaft 56, the latch 94 being coextensive with the longitudinal axis of the bifurcated lever 84. The end portion of latch 94 is provided with a rounded surface 98 and a flat surface 100, the flat surface 100 normally engaging the flat surface 82 of the bell crank striker 66. A pair of transverse carn followers 102 are formed on the side edges of the latch 94 for engaging a cam surface 104 formed on the support member 42.

A second shaft 106 is secured to the support member 42 by a pair of counterbored apertures 108 slotted as at 189, the shaft 106 being secured to the support member 42 in a manner similar to that of shaft 56. A muting lever 110, as best illustrated in FIGURES 3 and 5, is pivotally secured to the shaft 106 and is spring biased into engagement with the bifurcated lever 84 by a spring 112 engaging the mutinglever 110 and a lug 114 formed on the support member 42. The muting lever 110 is provided with a leg 116 which normally contacts a lateral surface of the vibrator rod 36 to serve as a vibration damper when the bifurcated lever is in an unactuated position, as described and claimed in Adler Patent No. 2,821,954, assigned to the present assignee. Such muting levers may be desired to prevent undesired double actuation of such functions as channel selection or stepped volume adjustment, but are not ordinarily provided in association with vibrator rods employed to perform single step operating functions such as turning the receiver on or off, or muting the audio portion of the received telecast.

The operation of the signal generator 10 is best illustrated in FIGURES 3 and 3a, the former showing the signal generator in an unactuated position and the latter showing the signal generator in a partially actuated position. When it is desired to actuate a selected one of the vibrator rods 36, the push button 28 associated therewith is depressed and released. As the push button 28 is depressed, the bifurcated lever 84 to which it is secured is rotated clockwise about the shaft 56. The latch 94, being slidably received within the bifurcated lever 84 and engaging the fiat surface 82 of the bell crank striker 66, causes the bell crank 66 to rotate with the bifurcated lever 84 about the shaft 56. As the button 28 is depressed and the bifurcated lever 84 and bell crank striker 66 are r0- tated clockwise about the shaft 56, the latch 94 is cammed away from the shaft 56 against the urging of spring 96 by the cam follower 102 riding along the inclined cam surface 104 formed on the support member 42. The bell crank striker 66 is thus caused to rotate about the shaft 56 against the urging of spring 74 until the latch 94 is camrned out of engagement with the flat surface 82, whereupon the bell crank striker 66 is released and caused to rotate counterclockwise about shaft 56 by the urging of spring 74 thereby propelling the hammer 52 through the guide channel 48 and into contact with the vibrator rod 36. The first leg 68 of the bell crank striker 66 is restrained from further rotation by the end of the slot 72. After the ferromagnetic hammer 52 strikes the end of the vibrator rod 36, the permanent magnets 50 disposed on either side of the guide channel 48 cause the hammer 52 to return through the guide channel 48 until it abuts the first leg 68 of the bell crank striker 66.

The spring 112 on the muting lever 110 causes the end of the muting lever 110- to abut the end of the bifurcated lever 84 and urges the bifurcated lever 84 towards its unactuated position. In this position, the end 116 of the muting lever 110 contacts the vibrator rod 36 to damp vibrations therein. However, upon actuation of the push button 28 and rotation of the bifurcated lever 84, the end 116 of the muting lever 110 is rotated out of contact with the vibrator rod 36 during the interval of time that the vibrator rod 36 is struck by the hammer 52. Upon release of the button 28, the spring 112 urges the bifurcated lever 84 towards its unactuated position, thereby allowing the muting lever 110 to rotate counterclockwise about the shaft 106 and cause the end 116 of the muting lever 110 to again contact and damp vibrations in the vibrator rod 36. As the bifurcated lever 84 is rotating towards its unactuated position under the influence of spring 112, the rounded surface 98 of the latch 94 engages the rounded surface of the bell crank striker 66 and earns the latch in a direction away from the shaft 56 against the bias of spring 96 so that the end of the latch 94 passes around the end of the second leg 70 of the bell crank striker 66. Once around the end of the bell crank striker 66 the latch 94 is caused to slide towards the shaft 56 and into engagement with the flat surface 82 of the bell crank striker 66 by the urging of spring bias means 96, thereby positioning the latch 94 for the next actuation.

Although the signal generator has been primarily described in connection with the construction and operation of but a single actuator mechanism and vibrator rod, it should be understood that the remaining actuators and vibrators are identical to the one described except for the different lengths of the vibrator rods. In the embodiment of the invention illustrated in the drawings, four such actuator and vibrator combinations are shown, however, either a greater or a lesser number may be provided depending upon the number of functions desired to be remotely controlled, and the damper element 116 may be omitted in connection with some or all of the rods as desired.

There has thus been described an ultrasonic signal generator for use in a remote control system which is capable of selectively generating one of a plurality of ultrasonic signals for selectively actuating a corresponding plurality of control functions. The ultrasonic signal generator of the present invention provides novel means for actuating the hammer element, which means allows for a more compact assemblage of necessary components and a degree of reliability not heretofore attainable. This is primarily accomplished by providing a common pivotal axis for both the bell crank striker 66 and the bifurcated lever 84 and by combining a vibration damper and bifurcated lever spring bias means in a single muting lever 110.

While only a particular embodiment of the invention has been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and, therefore, the aim of the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention.

I claim:

1. A portable hand-held signal generator for use in a remote control system comprising:

mechanically excitable vibrator means;

a support member having a guide channel therein, said guide channel having an opening terminating adjacent said vibrator means;

a hammer slidably received within said guide channel;

means captivating said hammer Within said guide channel;

a shaft secured to said support member;

striker means pivotally mounted on said shaft;

spring bias means associated with said striker means for urging said striker means towards said hammer;

actuator means pivotally mounted on said shaft for rotating said striker means against the urging of said spring bias means; and

trip means mounted on said actuator means for releasing said striker means after rotation of the latter through a predetermined angular displacement, thereby allowing said spring bias means to rotate said striker means and cause said hammer to be propelled through said guide channel and into contact with said vibrator means for initiating vibrations therein.

2. A signal generator in accordance with claim 1 wherein:

said striker means comprises a bell crank having first and second legs, said bell crank being pivotally mounted on said shaft intermediate said legs, said first leg being disposed adjacent said hammer;

and said actuator means comprises a bifurcated lever having a pair of arms pivotally mounted on said shaft on opposite sides of the intermediate portion of said bell crank, said lever having means secured thereto for manual actuation.

3. A signal generator in accordance with claim 2 further comprising:

a muting lever pivotally mounted on said support member the opposite ends of said muting lever respectively contacting said bifurcated lever and said vibrator means when said bifurcated lever is in an unactuated position, said bifurcated lever rotating said muting lever out of contact with said vibrator means as the bifurcated lever and the bell crank are simultaneously rotated, said muting lever being spring biased for urging the bifurcated lever towards an unactuated position.

4. A signal generator in accordance with claim 1 wherein:

said support member is provided with a cam surface;

and

said trip means comprises a latch slidably received within said actuator means, said latch being provided with a cam follower which engages said cam surface for sliding said latch in a direction away from said shaft as said lever is rotated.

5. A signal generator in accordance with claim 4 wherein:

said latch is biased into engagement with said striker means for rotating the latter as said actuator means is rotated, said latch being subsequently cammed out of engagement with said striker means by said cam surface to release the latter after rotation through said predetermined angular displacement.

6. A signal generator in accordance with claim 5 wherein:

the end of said striker means adjacent said latch is provided with a rounded surface for camming said latch around the end of said striker means as said actuator means is rotated towards an unactuated position.

7. A portable hand-held ultrasonic signal generator for use in a remote control system, which signal generator comprises:

a mechanically excitable cylindrical vibrator rod;

a support member having a cam surface thereon and a cylindrical guide channel therein, said guide channel having a central axis substantially coincident with the axis of said vibrator rod, said guide channel terminating a predetermined distance from one end of said vibrator rod;

a cylindrical ferromagnetic hammer slidably received Within said guide channel, said hammer having a length greater than said predetermined distance;

permanent magnet means establishing a magnetic field traversing said guide channel for magnetically captivating said ferromagnetic hammer;

a shaft mounted on said support member;

a bell crank striker having first and second legs and being pivotally mounted intermediate said legs on said shaft, the end of said second leg having a rounded surface and a fiat surface;

spring bias means for urging the first leg of said bell crank in a direction towards said hammer;

a manually operable push button;

a bifurcated lever secured to said push button, said lever having a pair of arms pivotally mounted on said shaft on either side of said bell crank, said lever being movable through a path from a first unactuated position to a second actuated position as said push button is depressed;

a latch slidably received within said bifurcated lever, said latch being spring biased towards said shaft and coextensive with the longitudinal axis of said bifurcated lever, said latch having a pair of transverse cam followers extending from the side edges thereof for engaging the cam surface on said support member, said latch having an end portion with a rounded surface and a fiat surface, the flat surface of said latch engaging the fiat surface of said bell crank for rotating the latter against the urging of said spring bias means as said button is depressed, said latch bewith said rod when said lever is in its actuated posiing cammed out of engagement with said bell crank tion.

upon rotation of the latter through'a predetermined References Cited angular distance to allow the bell crank to rotate un- UNITED STATES PATENTS der the urging of said spring bias means and to propel 5 the hammer through said guide channel and into img zwss 1 pact With said rod to initiate vibrations therein, said g g g /523 a is al rounded surfaces of said bell crank and latch subse- 2'979022 1/1961 1011a 116*137 quently camming said latch around the end of said 3017849 1/1962 g g ig f 116 137 bell crank as said lever is rotated towards its un- 10 3O54380 9/1962 Sielafi r W Posmon; and 3,118,423 1/1964 Schmid 116-137 means prvotally secured to sald support member for 3 164 1/1965 Schmid 116 137 urging said lever towards its unactuated position, said 3:165:O90 1/1965 Smith 116 137 means contacting said vibrator rod when said lever 3,189,000 6/1965 Salners is in its unactuated position to damp vibrations therein and being pivoted to a position out of contact LOUIS I. CAPOZI, Primary Examiner. 

1. A PORTABLE HAND-HELD SIGNAL GENERATOR FOR USE IN A REMOTE CONTROL SYSTEM COMPRISING: MECHANICALLY EXCITABLE VIBRATOR MEANS; A SUPPORT MEMBER HAVING A GUIDE CHANNEL THEREIN, SAID GUIDE CHANNEL HAVING AN OPENING TERMINATING ADJACENT SAID VIBRATOR MEANS; A HAMMER SLIDABLY RECEIVED WITHIN SAID GUIDE CHANNEL; MEANS CAPTIVATING SAID HAMMER WITHIN SAID GUIDE CHANNEL; A SHAFT SECURED TO SAID SUPPORT MEMBER; STRIKER MEANS PIVOTALLY MOUNTED ON SAID SHAFT; SPRING BIAS MEANS ASSOCIATED WITH SAID STRIKER MEANS FOR URGING SAID STRIKER MEANS TOWARDS SAID HAMMER; ACTUATOR MEANS PIVOTALLY MOUNTED ON SAID SHAFT FOR ROTATING SAID STRIKER MEANS AGAINST THE URGING OF SAID SPRING BIAS MEANS; AND TRIP MEANS MOUNTED ON SAID ACTUATOR MEANS FOR RELEASING SAID STRIKER MEANS AFTER ROTATION OF THE LATTER THROUGH A PREDETERMINED ANGULAR DISPLACEMENT, THEREBY ALLOWING SAID SPRING BIAS MEANS TO ROTATE SAID STRIKER MEANS AND CAUSE SAID HAMMER TO BE PROPELLED THROUGH SAID GUIDE CHANNEL AND INTO CONTACT WITH SAID VIBRATOR MEANS FOR INITIATING VIBRATIONS THEREIN. 